Prediction, assessment, and management of suboptimal GnRH agonist trigger: a systematic review

Purpose This systematic review aimed to identify baseline patient demographic and controlled ovarian stimulation characteristics associated with a suboptimal response to GnRHa triggering, and available options for prevention and management of suboptimal response. Methods PubMed, Google Scholar, Medline, and the Cochrane Library were searched for keywords related to GnRHa triggering, and peer-reviewed articles from January 2000 to September 2021 included. Results Thirty-seven studies were included in the review. A suboptimal response to GnRHa triggering was more likely following long-term or recent oral contraceptive use and with a low or high body mass index. Low basal serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol serum levels were correlated with suboptimal oocyte yield, as was a low serum LH level on the day of triggering. A prolonged stimulation period and increased gonadotropin requirements were correlated with suboptimal response to triggering. Post-trigger LH < 15 IU/L best correlated with an increased risk for empty follicle syndrome and a lower oocyte retrieval rate. Retriggering with hCG may be considered in patients with suboptimal response according to post-trigger LH, as in cases of failed aspiration. Conclusion Pre-treatment assessment of patient characteristics, with pre- and post-triggering assessment of clinical and endocrine cycle characteristics, may identify cases at risk for suboptimal response to GnRHa triggering and optimize its utilization.